Guided punch for talar augments

ABSTRACT

A guided punch is disclosed. The guided punch generally comprises a strike cap comprising a strike surface, a punch comprising a distal cutting edge, and a guide rod. The strike cap defines a first cavity therein. The punch defines a second cavity therein in communication with the first cavity. The guide rod is located within the first and second cavities and extends a predetermined distance beyond the distal cutting edge of the punch. The strike cap and the punch are moveable relative to the guide rod.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/404,818, filed Dec. 1, 2014, which is a national phase entry under 35U.S.C. 371 of International Patent Application PCT/US2014/065786, filedNov. 14, 2014, the entireties of which are herein incorporated byreference.

FIELD OF THE INVENTION

The present disclosure is generally related to osteopathic surgery. Morespecifically, the present disclosure is related to talar augmentation.

BACKGROUND

Some surgical procedures utilize implants having a stem or otherprotrusion for anchoring the implant to a bone. For example, in totalankle replacement, a talar dome may have a stem extending from a bottomsurface into the talas. The stem is configured to maintain the implantin a predetermined orientation with respect to the bone and provideadditional fixation into the talus. In order to attach the implant, ahole must be formed in the bone to receive the implant.

Formation of the hole by, for example, a drill, may result in an unevenhole. Current formation techniques do not allow for the formation ofholes having non-circular shapes such as, for example, square holes, toreceive implants and/or stems.

SUMMARY

In various embodiments, a guided punch is disclosed. The guided punchgenerally comprises a strike cap comprising a strike surface, a punchcomprising a distal cutting edge, and a guide rod. The strike capdefines a first cavity therein. The punch defines a second cavitytherein. The second cavity is in communication with the first cavity.The guide rod is located within the first and second cavities andextends a predetermined distance beyond the distal cutting edge of thepunch. The strike cap and the punch are moveable relative to the guiderod.

In various embodiments, a method for reaming a hole is disclosed. Themethod generally comprises forming a pilot hole in a bone, inserting aguide rod of a guided punch into the pilot hole and reaming the pilothole to a uniform hole using the guided punch. The guided punchcomprises a strike cap, a punch coupled to a distal end of the strikecap and having a distal cutting edge. The guide rod extends apredetermined distance beyond the distal cutting edge of the punch. Thestrike cap and the punch are moveable relative to the guide rod.

In various embodiments, a surgical system is disclosed. The surgicalsystem generally comprises a guided punch assembly, a first punch, and asecond punch. The guide punch assembly comprises a strike cap comprisinga strike surface. The strike cap defines a first cavity therein. A guiderod is located within the first cavity and extends a predetermineddistance beyond a distal edge of the strike cap. A spring is disposedbetween the guide rod and a surface of the first cavity. The spring isconfigured to exert a proximal biasing force on the strike cap. Thefirst punch is configured to couple to the strike cap and comprises afirst size, a first shape, and a first depth. The second punch isconfigured to couple to the strike cap and comprises a second size, asecond shape, and a second depth.

BRIEF DESCRIPTION OF THE FIGURES

The features and advantages of the present invention will be more fullydisclosed in, or rendered obvious by the following detailed descriptionof the preferred embodiments, which are to be considered together withthe accompanying drawings wherein like numbers refer to like parts andfurther wherein:

FIG. 1 illustrates a guided punch assembly.

FIG. 2. illustrates a guide pin of the guided punch assembly of FIG. 1.

FIG. 3 illustrates a punch of the guided punch assembly of FIG. 1.

FIG. 4 illustrates a strike cap of the guided punch assembly of FIG. 1.

FIG. 5 illustrates formation of a pilot hole in a bone.

FIG. 6 illustrates a guided punch assembly located within a pilot holeformed in the bone.

FIG. 7 illustrates a cross-sectional view of the guided punch assemblyof FIG. 6 in initial position.

FIG. 8 illustrates a cross-sectional view of the guided punch assemblyof FIG. 6 in a punched position.

FIG. 9 is a flowchart illustrating one embodiment of a method of reaminga hole in a bone.

DETAILED DESCRIPTION

The description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. In the description, relativeterms such as “lower,” “upper,” “horizontal,” “vertical,” “proximal,”“distal,” “above,” “below,” “up,” “down,” “top” and “bottom,” as well asderivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,”etc.) should be construed to refer to the orientation as then describedor as shown in the drawing under discussion. These relative terms arefor convenience of description and do not require that the apparatus beconstructed or operated in a particular orientation. Terms concerningattachments, coupling and the like, such as “connected” and“interconnected,” refer to a relationship wherein structures are securedor attached to one another either directly or indirectly throughintervening structures, as well as both movable or rigid attachments orrelationships, unless expressly described otherwise.

The present disclosure generally provides a guided punch assemblyconfigured for preparing a bone for insertion of an implant, such as,for example, a talar augment. The various embodiments of the guidedpunch assembly disclosed herein generally comprise a guide pin having apunch slideably positioned about a portion of the guide pin. A strikecap is coupled to the punch. The strike cap and the punch are slideablymoveable along a longitudinal length of the guide pin. The punch isconfigured to ream a hole in a bone, such as, for example, a talas.

FIG. 1 illustrates a guided punch assembly 2. The guided punch assembly2 comprises a guide pin 4. The guide pin 4 may comprise any suitableshape, such as, for example, a cylinder. The guide pin 4 is sized andconfigured to fit within a pilot hole formed by a drill in a bone, suchas, for example, a talas. In some embodiments, the guide pin 4 comprisesa hollow cavity for receiving a spring therein (see FIG. 7). The guidepin 4 comprises a distal tip 10 configured to contact a bottom surfaceof the pilot hole. In some embodiments, the distal tip 10 comprises anub configured to be received within a k-wire hole to center the punchassembly 2 in the pilot hole.

The guide punch assembly 2 further comprises a punch 6. The punch 6comprises an internal cavity or channel (not shown) for receiving theguide pin 4 therein. The punch 6 is concentrically located about aportion of the guide pin 4. The punch 6 is configured to ream a bonesection to receive an implant and/or augment. The distal edge of thepunch 6 comprises a reaming edge 12 configured to ream a bone. When thepunch 6 is driven distally, the reaming edge 12 reams a hole sized andconfigured to receive the implant. One or more openings 14 a, 14 b areformed about the periphery of the punch 6 to allow for evacuation ofbone matter during reaming and for indication of reaming depth. Thepunch 6 is movable with respect to the guide pin 4. For example, in theillustrated embodiment, the punch 6 is slideably moveable in aproximal/distal direction over the guide pin 4 such that the punch 6 ismoveable along a longitudinal axis of the guide pin 4 while the guidepin 4 remains stationary. The punch 6 may comprise any suitablecross-sectional shape, such as, for example, square, circular,hexagonal, and/or any other suitable shape. In some embodiments, thecross-sectional shape of the punch 6 corresponds to a cross-sectionalshape of an implant to be received within the reamed hole.

A strike cap 8 is fixedly coupled to a proximal side of the punch 6. Thestrike cap 8 is configured to drive the reaming edge 12 of the punch 6into a bone. The strike cap 8 comprises a strike surface 16. The strikesurface 16 provides a flat surface configured to be struck by aninstrument, such as a hammer, to exert sufficient force on the punch 6to drive the reaming edge 12 to a predetermined depth within the bone.The strike cap 8 may also comprise a gripping section 18. The grippingsection 18 may comprise, for example, an inset or concave surfaceconfigured to provide a firm grip to a clinician and/or a gripping tool.The strike cap 8 may be coupled to the punch 6 by any suitableconnection, such as, for example, a threaded connection, a weldedconnection, a press-fit connection, and/or any other suitableconnection. In some embodiments, the punch 6 is selectively separablefrom the strike cap 8. For example, in some embodiments, the punch 6comprises a first interchangeable punch coupled to the strike cap 8 by aplurality of threads. The first interchangeable punch may be removedfrom the strike cap 8 and replaced by a second interchangeable punchhaving, for example, a different size, shape, and/or predetermineddepth. It will be recognized that any number of interchangeable puncheshaving various sizes, shapes, depths, and/or other parameters may beselectively coupled to the guide punch assembly 2.

In operation, the guided punch assembly 2 is positioned at a treatmentsite by inserting the guide pin 4 into a pilot hole and the reaming edge12 is driven into a bone section by striking the strike surface 16 ofthe strike cap 8 with sufficient force, for example, by using a hammer.The strike cap 8 may comprise a lip 20 configured to prevent the punch 6from extending into a bone beyond a predetermined depth. The lip 20contacts the bone outside of the reamed hole and prevents furtherdriving of the punch 6 beyond a predetermined depth. In someembodiments, a spring (see FIG. 7) is located within an internal cavityof the guide pine 4 to bias the punch 6 and the strike cap 8 in aproximal direction. When the strike cap 8 is struck, the strike cap 8and the punch 6 are driven distally to the predetermined depth definedby the lip 20. The spring is compressed and exerts a proximal force toreturn the punch 6 and the strike cap 8 to a proximal-most (or initial)position.

FIG. 2 illustrates one embodiment of a guide pin 4. The guide pin 4comprises a shaft 22 having a distal tip 10 and a proximal lip 24. Theshaft 22 and the distal tip 10 are sized and configured to be receivedwithin a pre-drilled pilot hole. The shaft 22 extends a predeterminedlength along a longitudinal axis. The length of the shaft 22 correspondsto the depth of the hole to be reamed in the bone and the length of thestrike cap 8. For example, in some embodiments, the length of the shaft22 is configured to extend from the strike surface 16 of the strike cap8 to the reaming edge 12 of the punch 6. The distal tip 10 is configuredto contact the bottom of the pilot hole and may comprise a nub (see FIG.7) configured to interface with a k-wire hole to center the guide pin 4in the pilot hole. A proximal lip 24 is located at the proximal end ofthe guide pin 4. The proximal lip 24 comprises a section having a widerdiameter than the shaft. In some embodiments, the proximal lip 24 isconfigured to support a spring located within an inner cavity defined bythe strike cap 8 and/or is configured to maintain the guide pin 4 withinthe punch 6 and strike cap 8 when the punch assembly 2 is fullyassembled. In some embodiments, the guide pin 4 defines a cavityconfigured to receive a spring therein. The cavity is defined by anopening on the proximal end of the guide pin 4 and extends at leastpartially into the shaft 22.

FIG. 3 illustrates one embodiment of a punch 6. The punch 6 comprises areaming section 26 and a coupling section 28. The reaming section 26 issized and configured to ream a hole into a bone. The reaming section 26defines a distal reaming edge 12. A distal opening 30 is configured toreceive a bone section during reaming. The coupling section 28 isconfigured to couple the punch 6 to a strike cap 8. In the illustratedembodiment, the coupling section 28 comprises a plurality of threads,although it will be recognized that any suitable coupling feature may beused. A channel extends through the coupling section 28 and the distalopening 30 to allow the punch 6 to slide over the guide pin 4. The punch6 may comprise any suitable material, such as, for example, stainlesssteel.

FIG. 4 illustrates one embodiment of a strike cap 8. The strike cap 8comprises an internal cavity 34 having a distal opening configured toreceive the coupling section 28 and the guide pin 4 therein. The distalopening may comprise one or more mating features to couple the strikecap 8 to the punch 6. For example, in the illustrated embodiment, thedistal opening 35 of the strike cap 8 comprises an internal threading 36configured to couple to the external threads 32 of the punch 6 (see FIG.3). In some embodiments, the strike cap 8 is detachable from the punch 6to allow two or more interchangeable punches to be used with the strikecap 8. The distal end of the strike cap 8 further defines a lip 20. Thelip 20 is configured to prevent a punch 6 coupled to the strike cap 8from being driven beyond a predetermined depth into a bone section. Thestrike cap 8 may be configured to receive a spring within the internalcavity 34 to provide a proximal bias to the strike cap 8 and the punch 6with respect to the guide pin 4 when the punch assembly 2 is fullyassembled.

FIGS. 5-8 illustrate various stages of forming a hole in a bone 152 of ajoint 100 using a guided punch assembly 102. FIG. 9 is a flowchartillustrating one embodiments of a method 200 of forming the hole in abone. FIG. 5 illustrates a first bone 150 and a second bone 152. Thefirst bone 150 has a resected section 154. The second bone 152 comprisesa resected section 156. In a first step 202, a k-wire 158 is insertedthrough a portion of the second bone 152. The k-wire 158 acts as a guidefor a drill 160. In a second step 204, the drill 160 inserted over thek-wire 158 and rotated via shaft 162 to form a pilot hole 164 in thesecond bone 152. The pilot hole 164 comprises a first diameter. Thedrill 160 and the k-wire 158 are removed after forming the pilot hole164.

After forming the pilot hole 164, a punch assembly 102 is positioned atthe treatment site in a third step 206. FIG. 6 illustrates the punchassembly 102 in an initial position. The guide pin 104 of the punchassembly 102 is inserted into the pilot hole 164 formed in the secondbone 152. In various embodiments, the diameter of the guide pin 104 maybe equal to or smaller than the diameter of the pilot hole 164. FIG. 7illustrates a cross-sectional view of the second bone 152 and the punchassembly 102. As shown in FIG. 7, the guide pin 104 is positioned withinthe pilot hole 164. A nub 166 may be coupled to the distal tip of theguide pin 104. The nub 166 is sized and configured to fit within a hole168 left by the k-wire 158. The nub 166 centers the guide pin 104 withinthe pilot hole 164. In some embodiments, the guide pin 104 comprises alength such that the cutting edge 112 of the punch 106 rests against thesecond bone 152 when the guide pin 104 is inserted into the pilot hole164. The punch 106 is coupled to a strike cap 108 by a threadedconnection 32.

In a fourth step 208, once the punch assembly 102 is positioned in thepilot hole 164, the strike surface 116 of the strike cap 108 is struckby, for example, a hammer, to drive the punch 106 to a distal-mostposition as shown in FIG. 8. The punch 106 is driven into the secondbone 152 by the strike cap 108. The punch 106 removes a bone section toream a uniform hole 174 in the second bone 152. The punch 106 and thestrike cap 108 move relative to the guide pin 104, which remainsstationary. A spring 172 located within the strike cap 108 iscompressed. In some embodiments, the spring 172 is located within aspring recess 170 formed in the guide pin 104. The spring 172 drives thestrike cap 108 and the punch 106 proximally after the reamed hole 174 isformed. The reamed hole 174 comprises a uniform hole having a size andshape matching the size and shape of the punch 106. In a fifth step 210,the punch assembly 102 is removed from the reamed hole 174 and animplant is inserted therein (not shown). In some embodiments, the punch106 comprises a first punch having a first size, a first shape, and afirst depth. The first punch may be detached from the strike cap 108 by,for example, rotating the external threads of the first punch out of theinternal threads of the strike cap 108. A second punch comprising atleast one of a second size, a second shape, and/or a second depth may becoupled to strike cap 108. The second punch may be used to ream a secondhole having a size, shape, and/or depth different than the first reamedhole 174.

In various embodiments, a guided punch is disclosed. The guided punchgenerally comprises a strike cap comprising a strike surface, a punchcomprising a distal cutting edge, and a guide rod. The strike capdefines a first cavity therein. The punch defines a second cavitytherein in communication with the first cavity. The guide rod is locatedwithin the first and second cavities and extends a predetermineddistance beyond the distal cutting edge of the punch. The strike cap andthe punch are moveable relative to the guide rod.

In some embodiments, the guide punch comprises a spring located in thefirst cavity and configured to bias the strike cap and the punch to aproximal-most position.

In some embodiments, the punch comprises one or more holes configured toreceive bone material therein.

In some embodiments, the punch is coupled to the strike cap by athreaded connection.

In some embodiments, the guide rod is sized and configured to bereceived within a pilot hole formed in a bone.

In some embodiments, the guide rod comprises a nub on a distal end sizedand configured to interface with a k-wire hole.

In some embodiment, the bone comprises a talas.

In some embodiments, the strike cap comprises a distal lip sized andconfigured to prevent the punch from being driven beyond a predetermineddepth.

In various embodiments, a method for reaming a hole is disclosed. Themethod generally comprises forming a pilot hole in a bone, inserting aguide rod of a guided punch into the pilot hole and reaming the pilothole to a uniform hole using the guided punch. The guided punchcomprises a strike cap, a punch coupled to a distal end of the strikecap and having a distal cutting edge. The guide rod extends apredetermined distance beyond the distal cutting edge of the punch. Thestrike cap and the punch are moveable relative to the guide rod.

In some embodiments, the step of forming the pilot hole comprisesinserting a k-wire through the bone, inserting a drill over the k-wire,and rotating a drill head of the drill to form the pilot hole in thebone.

In some embodiments, the step of reaming the pilot hole comprisesstriking a strike surface of the strike cap to drive the strike cap andthe punch distally.

In some embodiments, the step of reaming the pilot hole furthercomprises compressing, by the strike cap, a spring located within acavity of the strike cap and returning, by the spring, the strike capand the punch to a proximal-most position.

In some embodiments, the method further comprises, prior to insertingthe guide rod into the pilot hole, a step of assembling the guide punch.Assembling the guide punch comprises: inserting the guide rod into aninternal cavity of the strike cap, sliding the punch over the guide rod,and coupling the punch to the strike cap.

In some embodiments, the punch comprises a first punch. The first punchcomprises a first depth, a first size, and a first shape. The methodfurther comprises removing the first punch from the strike cap andcoupling a second punch to the strike cap. The second punch comprises asecond depth, a second size, and a second shape.

In various embodiments, a surgical system is disclosed. The surgicalsystem generally comprises a guided punch assembly, a first punch, and asecond punch. The guide punch assembly comprises a strike cap comprisinga strike surface. The strike cap defines a first cavity therein. A guiderod is located within the first cavity and extends a predetermineddistance beyond a distal edge of the strike cap. A spring is disposedbetween the guide rod and a surface of the first cavity. The spring isconfigured to exert a proximal biasing force on the strike cap. Thefirst punch is configured to couple to the strike cap and comprises afirst size, a first shape, and a first depth. The second punch isconfigured to couple to the strike cap and comprises a second size, asecond shape, and a second depth.

In some embodiments, the strike cap comprises an internal thread in thefirst cavity and each of the first and second punches comprise anexternal thread configured to couple to the internal thread of thestrike cap.

In some embodiments, the guide rod is sized and configured to bereceived within a pilot hole formed in a bone.

In some embodiments, the first size, first shape, and the first depth ofthe first punch correspond to a first implant.

In some embodiments at least one of the second size, the second shape,and the second depth is different from respective first size, firstshape, or first depth.

In some embodiments, the strike cap comprises a distal lip configured toprevent a punch coupled to the strike cap from exceeding a predetermineddepth

Although the subject matter has been described in terms of exemplaryembodiments, it is not limited thereto. Rather, the appended claimsshould be construed broadly, to include other variants and embodiments,which may be made by those skilled in the art.

What is claimed is:
 1. A method for performing surgery comprising:providing a device comprising: a strike cap comprising a strike surface,wherein the strike cap defines a first cavity therein; a punch coupledto a distal end of the strike cap, the punch comprising a distal cuttingedge, and wherein the punch defines a second cavity therein incommunication with the first cavity; a guide rod located within thefirst and second cavities and extending a predetermined distance beyondthe distal cutting edge of the punch, wherein the strike cap and thepunch are moveable relative to the guide rod, wherein the guide roddefines a proximal lip configured to interact with a proximal surface ofthe punch to maintain the guide rod at least partially within the firstcavity; and a spring positioned proximally of the guide rod within thefirst cavity, wherein the spring is configured maintain the guide rod ina fixed position with respect to a bone when the strike cap and punchare moved relative to the guide rod in response to an impaction force;forming a pilot hole in a bone; inserting a guide rod of a guided punchinto the pilot hole, wherein the guided punch comprises a strike cap, apunch coupled to a distal end of the strike cap and having a distalcutting edge, wherein the guide rod extends a predetermined distancebeyond the distal cutting edge of the punch, and wherein the strike capand the punch are moveable relative to the guide rod, wherein the guiderod defines a proximal lip configured to interact with a proximalsurface of the punch to maintain the guide rod at least partially withinthe first cavity, and a spring positioned proximally of the guide rodwithin the first cavity; and reaming the pilot hole to a uniform holeusing the guided punch, wherein the spring maintains the guide rod in afixed position with respect to a bone when an impaction force is appliedto the strike surface of the strike cap.
 2. The method of claim 1,wherein forming the pilot hole comprises: inserting a k-wire through thebone; inserting a drill over the k-wire; and rotating a drill head ofthe drill to form the pilot hole in the bone.
 3. The method of claim 1,wherein reaming the pilot hole comprises striking a strike surface ofthe strike cap to drive the strike cap and the punch distally.
 4. Themethod of claim 3, wherein reaming the pilot hole further comprises:compressing, by the strike cap, a spring located within a cavity of thestrike cap; and returning, by the spring, the strike cap and the punchto a proximal-most position.
 5. The method of claim 1, furthercomprising, prior to inserting the guide rod into the pilot hole, a stepof assembling the guide punch, wherein assembling the guide punchcomprises: inserting the guide rod into an internal cavity of the strikecap; sliding the punch over the guide rod; and coupling the punch to thestrike cap.
 6. The method of claim 5, wherein the punch comprises afirst punch, wherein the first punch comprises a first depth, a firstsize, and a first shape, wherein the method further comprises: removingthe first punch from the strike cap; and coupling a second punch to thestrike cap, wherein the second punch comprises a second depth, a secondsize, and a second shape.